Which came first??

[Blygy]

I'm building a new fuel system in my Power Wagon. (Dropped the block and trany off at the machine shop so now I gotta get my but in gear and figure it all out)

so now do I put the electric pump before or after the fuel filter??

also I'm running 1/2 inch line. It's probably a little large for my application (440 the engine builder is guessing over 400hp easy and almost 500 torque) I'm running a 770 cfm Holley truck avenger carb. Do I need a return line??

this truck was on propane so I have to build a new fuel system from scratch I have a tank in the box and the pump and filter will be mounted there as well.

Any other thoughts would be appreciated..

Thanx

Blygy

[kenabody]

Since most electric fuel pumps (that I'm aware of) are most efficient when pushing fuel forward, I would place the filter somewhere on the "out" or discharge side of the fuel pump. This is the reason why most aftermarket fuel pumps like to be mounted as close as possible to the fuel tank.

[451Mopar]

You don't mention the type of pump, but most of the good georotor pumps pull fairly good so you can put a filter before the pump which will make the pump last longer. Like kenabody said, the pumps are better at pushing fuel so you should mount the filter and pump close to the fuel tank.
If you run a big higher pressure fuel pump you may have to run a return line. Either way a by-pass regulator and return line allows the fuel pump to work at full volume so it runs cooler and the circulating fuel will be nice and cool when it go to the carb, so I would do the return line if you can. Also make sure the tank has a good vent.

My system runs like this:
Fuel cell to #8AN line to Mallory 500 Fuel Filter to Mallory 250 GPH fuel pump, #8AN line from pump (rear of car) to by-pass regulator (at engine.) From the regulator I run two #6AN lines, one to the front fuel bowl and one to the rear fuel bowl of the Holley Carb. The return line from the regulator is #8AN back to the top of the fuel cell. The fuel cell has a 3/8" vent line.
I have been running this fuel system for 5-years with no problems (other than the fuel pump is loud!)

[Blygy]

oops.. it's a carter electric.. P4070..Here's what summit has to say about it..
......................................
Vendor: Carter/Federal Mogul
Product Line: Carter Electric Fuel Pumps
Material: Steel

Keep your carb fed at high rpms.


72 gph, 4-6 psi, street style, electric fuel pump


With a free flow of 72 gph and 4-6 psi of fuel pressure, this Carter electric fuel pump will keep up with any carburetor. Racers will appreciate the pump's low 4.5 amp draw, too.
..............................................

Now that I look at it.. I'm not sure I like the 4-6 psi thing.. I thought it would be up around 9.. oh well I'll see how well it works and buy a different one if I need to..

also on the pump it says "don't use teflon tape on any fittings.. Do I use the creamy pipe dope then or nothing at all???I thought all pipe thread fittings shoulf use the tape or dope..

Blygy

[Kevin Garceau]

9 psi will push it through your stock needle and seats in a holley. I usually ran in the 7s and I was running in the 8s in the qtr mile.

[hchris6360]

I use the Holley Volumax pump. gearotor pump. I use both inlets with a fuel filter on each inlet. (Fram HPG1) I have a return line to the tank from the pump and 1/2 inch line to the regulator up by the carb. The pump was rated at 160 gph but I tested the system, filters and all, and it flowed over 190 gph. Since I am only making 510 hp it's more than enough. The regulator is set for 8 psi.

[dave571]

There is no need for high pressure, just the volume.

The only pressure delivering the fuel, from the carb to the engine, is atmospheric pressure, and the pressure differential produced by the flowing air.

The pressure of the fuel delivery pump, does not exist, after the fuel passes the needle and seat.

The carb itself is not pressurized.

[moparmotorman]

with 4-6 psi, you could do without a regulator & return line. i would put a fuel pressure guage near the carb just to be sure. or if you can , the isolated fuel[autometer] gauge so you can check fuel pressure under a full load.